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1.
CONTEXT: Inflammation is hypothesized to play a role in development of type 2 diabetes mellitus (DM); however, clinical data addressing this issue are limited. OBJECTIVE: To determine whether elevated levels of the inflammatory markers interleukin 6 (IL-6) and C-reactive protein (CRP) are associated with development of type 2 DM in healthy middle-aged women. DESIGN: Prospective, nested case-control study. SETTING: The Women's Health Study, an ongoing US primary prevention, randomized clinical trial initiated in 1992. PARTICIPANTS: From a nationwide cohort of 27 628 women free of diagnosed DM, cardiovascular disease, and cancer at baseline, 188 women who developed diagnosed DM over a 4-year follow-up period were defined as cases and matched by age and fasting status with 362 disease-free controls. MAIN OUTCOME MEASURES: Incidence of confirmed clinically diagnosed type 2 DM by baseline levels of IL-6 and CRP. RESULTS: Baseline levels of IL-6 (P<.001) and CRP (P<.001) were significantly higher among cases than among controls. The relative risks of future DM for women in the highest vs lowest quartile of these inflammatory markers were 7.5 for IL-6 (95% confidence interval [CI], 3.7-15.4) and 15.7 for CRP (95% CI, 6.5-37.9). Positive associations persisted after adjustment for body mass index, family history of diabetes, smoking, exercise, use of alcohol, and hormone replacement therapy; multivariate relative risks for the highest vs lowest quartiles were 2.3 for IL-6 (95% CI, 0.9-5.6; P for trend =.07) and 4.2 for CRP (95% CI, 1.5-12.0; P for trend =.001). Similar results were observed in analyses limited to women with a baseline hemoglobin A(1c) of 6.0% or less and after adjustment for fasting insulin level. CONCLUSIONS: Elevated levels of CRP and IL-6 predict the development of type 2 DM. These data support a possible role for inflammation in diabetogenesis.  相似文献
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36条目简明量表在中国人群中的适用性研究   总被引:113,自引:4,他引:109  
目的 探讨36条目简明量表(SF-36)在中国人群中的适用性。方法 评价SF-36在1603个农村居民、646个城市居民、70名中专女生、70名中专女生、70名中专女生、122名骨质疏松病人和150名中风患者中的信度与效度。结果 SF-36在中国人群中的信度和效度总体上可以接受,但不同领域的信度和效度不同,在不同人群中的测量信度和效度也不同。领域“躯体活动功能”、“躯体功能对角色功能的影响”、“疼痛”和“总体健康自评”的信度和效度要优于领域“活力”、“社会功能”、“情绪对角色功能的影响”和“心理健康”。农村人群的信度和效度比其他人群差。结论 SF-36可以在中国人群中应用,但必须注意不同特征人群的信度和效度差异,尤其在解释有关心理和社会功能测量领域的结果时要慎重。  相似文献
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"The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure" provides a new guideline for hypertension prevention and management. The following are the key messages(1) In persons older than 50 years, systolic blood pressure (BP) of more than 140 mm Hg is a much more important cardiovascular disease (CVD) risk factor than diastolic BP; (2) The risk of CVD, beginning at 115/75 mm Hg, doubles with each increment of 20/10 mm Hg; individuals who are normotensive at 55 years of age have a 90% lifetime risk for developing hypertension; (3) Individuals with a systolic BP of 120 to 139 mm Hg or a diastolic BP of 80 to 89 mm Hg should be considered as prehypertensive and require health-promoting lifestyle modifications to prevent CVD; (4) Thiazide-type diuretics should be used in drug treatment for most patients with uncomplicated hypertension, either alone or combined with drugs from other classes. Certain high-risk conditions are compelling indications for the initial use of other antihypertensive drug classes (angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, calcium channel blockers); (5) Most patients with hypertension will require 2 or more antihypertensive medications to achieve goal BP (<140/90 mm Hg, or <130/80 mm Hg for patients with diabetes or chronic kidney disease); (6) If BP is more than 20/10 mm Hg above goal BP, consideration should be given to initiating therapy with 2 agents, 1 of which usually should be a thiazide-type diuretic; and (7) The most effective therapy prescribed by the most careful clinician will control hypertension only if patients are motivated. Motivation improves when patients have positive experiences with and trust in the clinician. Empathy builds trust and is a potent motivator. Finally, in presenting these guidelines, the committee recognizes that the responsible physician's judgment remains paramount.  相似文献
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四川省城乡居民SF—36评价参考值   总被引:94,自引:2,他引:92  
目的 制定36条目简明量表(SF-36)参考值用于国内生命质量评价。方法 采用美国的评分标准及中国评分标准分别对四川省1603名农村居民和646名城市居民的生命质量进行评价,并与香港及美国常模比较。结果 中国评分标准与美国美国评分标准所得结果高度相关,8个领域的相关系数均在0.98以上,但两种评分标准所得结果的差异有显著性;四川省城乡居民SF-36评价结果与香港及美国常模比较,更接近香港评价值;不同年龄、性别及城乡人群之间的评分结果有显著性差异。结论 制定了四川省城乡不同性别及年龄居民的SF-36评价参考值,为在国内使用SF-36作为生命质量评价工具奠定了基础。  相似文献
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Context  Associations have been found between day-to-day particulate air pollution and increased risk of various adverse health outcomes, including cardiopulmonary mortality. However, studies of health effects of long-term particulate air pollution have been less conclusive. Objective  To assess the relationship between long-term exposure to fine particulate air pollution and all-cause, lung cancer, and cardiopulmonary mortality. Design, Setting, and Participants  Vital status and cause of death data were collected by the American Cancer Society as part of the Cancer Prevention II study, an ongoing prospective mortality study, which enrolled approximately 1.2 million adults in 1982. Participants completed a questionnaire detailing individual risk factor data (age, sex, race, weight, height, smoking history, education, marital status, diet, alcohol consumption, and occupational exposures). The risk factor data for approximately 500 000 adults were linked with air pollution data for metropolitan areas throughout the United States and combined with vital status and cause of death data through December 31, 1998. Main Outcome Measure  All-cause, lung cancer, and cardiopulmonary mortality. Results  Fine particulate and sulfur oxide–related pollution were associated with all-cause, lung cancer, and cardiopulmonary mortality. Each 10-µg/m3 elevation in fine particulate air pollution was associated with approximately a 4%, 6%, and 8% increased risk of all-cause, cardiopulmonary, and lung cancer mortality, respectively. Measures of coarse particle fraction and total suspended particles were not consistently associated with mortality. Conclusion  Long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopulmonary and lung cancer mortality.   相似文献
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Context  Statin drugs reduce both atherogenic lipoproteins and cardiovascular morbidity and mortality. However, the optimal strategy and target level for lipid reduction remain uncertain. Objective  To compare the effect of regimens designed to produce intensive lipid lowering or moderate lipid lowering on coronary artery atheroma burden and progression. Design, Setting, and Patients  Double-blind, randomized active control multicenter trial (Reversal of Atherosclerosis with Aggressive Lipid Lowering [REVERSAL]) performed at 34 community and tertiary care centers in the United States comparing the effects of 2 different statins administered for 18 months. Intravascular ultrasound was used to measure progression of atherosclerosis. Between June 1999 and September 2001, 654 patients were randomized and received study drug; 502 had evaluable intravascular ultrasound examinations at baseline and after 18 months of treatment. Interventions  Patients were randomly assigned to receive a moderate lipid-lowering regimen consisting of 40 mg of pravastatin or an intensive lipid-lowering regimen consisting of 80 mg of atorvastatin. Main Outcome Measures  The primary efficacy parameter was the percentage change in atheroma volume (follow-up minus baseline). Results  Baseline low-density lipoprotein cholesterol level (mean, 150.2 mg/dL [3.89 mmol/L] in both treatment groups) was reduced to 110 mg/dL (2.85 mmol/L) in the pravastatin group and to 79 mg/dL (2.05 mmol/L) in the atorvastatin group (P<.001). C-reactive protein decreased 5.2% with pravastatin and 36.4% with atorvastatin (P<.001). The primary end point (percentage change in atheroma volume) showed a significantly lower progression rate in the atorvastatin (intensive) group (P = .02). Similar differences between groups were observed for secondary efficacy parameters, including change in total atheroma volume (P = .02), change in percentage atheroma volume (P<.001), and change in atheroma volume in the most severely diseased 10-mm vessel subsegment (P<.01). For the primary end point, progression of coronary atherosclerosis occurred in the pravastatin group (2.7%; 95% confidence interval [CI], 0.2% to 4.7%; P = .001) compared with baseline. Progression did not occur in the atorvastatin group (–0.4%; CI –2.4% to 1.5%; P = .98) compared with baseline. Conclusions  For patients with coronary heart disease, intensive lipid-lowering treatment with atorvastatin reduced progression of coronary atherosclerosis compared with pravastatin. Compared with baseline values, patients treated with atorvastatin had no change in atheroma burden, whereas patients treated with pravastatin showed progression of coronary atherosclerosis. These differences may be related to the greater reduction in atherogenic lipoproteins and C- reactive protein in patients treated with atorvastatin.   相似文献
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CONTEXT: Peripheral arterial disease (PAD) is a manifestation of systemic atherosclerosis that is common and is associated with an increased risk of death and ischemic events, yet may be underdiagnosed in primary care practice. OBJECTIVE: To assess the feasibility of detecting PAD in primary care clinics, patient and physician awareness of PAD, and intensity of risk factor treatment and use of antiplatelet therapies in primary care clinics. DESIGN AND SETTING: The PAD Awareness, Risk, and Treatment: New Resources for Survival (PARTNERS) program, a multicenter, cross-sectional study conducted at 27 sites in 25 cities and 350 primary care practices throughout the United States in June-October 1999. PATIENTS: A total of 6979 patients aged 70 years or older or aged 50 through 69 years with history of cigarette smoking or diabetes were evaluated by history and by measurement of the ankle-brachial index (ABI). PAD was considered present if the ABI was 0.90 or less, if it was documented in the medical record, or if there was a history of limb revascularization. Cardiovascular disease (CVD) was defined as a history of atherosclerotic coronary, cerebral, or abdominal aortic aneurysmal disease. MAIN OUTCOME MEASURES: Frequency of detection of PAD; physician and patient awareness of PAD diagnosis; treatment intensity in PAD patients compared with treatment of other forms of CVD and with patients without clinical evidence of atherosclerosis. RESULTS: PAD was detected in 1865 patients (29%); 825 of these (44%) had PAD only, without evidence of CVD. Overall, 13% had PAD only, 16% had PAD and CVD, 24% had CVD only, and 47% had neither PAD nor CVD (the reference group). There were 457 patients (55%) with newly diagnosed PAD only and 366 (35%) with PAD and CVD who were newly diagnosed during the survey. Eighty-three percent of patients with prior PAD were aware of their diagnosis, but only 49% of physicians were aware of this diagnosis. Among patients with PAD, classic claudication was distinctly uncommon (11%). Patients with PAD had similar atherosclerosis risk factor profiles compared with those who had CVD. Smoking behavior was more frequently treated in patients with new (53%) and prior PAD (51%) only than in those with CVD only (35%; P <.001). Hypertension was treated less frequently in new (84%) and prior PAD (88%) only vs CVD only (95%; P <.001) and hyperlipidemia was treated less frequently in new (44%) and prior PAD (56%) only vs CVD only (73%, P<.001). Antiplatelet medications were prescribed less often in patients with new (33%) and prior PAD (54%) only vs CVD only (71%, P<.001). Treatment intensity for diabetes and use of hormone replacement therapy in women were similar across all groups. CONCLUSIONS: Prevalence of PAD in primary care practices is high, yet physician awareness of the PAD diagnosis is relatively low. A simple ABI measurement identified a large number of patients with previously unrecognized PAD. Atherosclerosis risk factors were very prevalent in PAD patients, but these patients received less intensive treatment for lipid disorders and hypertension and were prescribed antiplatelet therapy less frequently than were patients with CVD. These results demonstrate that underdiagnosis of PAD in primary care practice may be a barrier to effective secondary prevention of the high ischemic cardiovascular risk associated with PAD.  相似文献
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Plasma adiponectin levels and risk of myocardial infarction in men   总被引:65,自引:0,他引:65  
Context  Adiponectin, a recently discovered adipocyte-derived peptide, is involved in the regulation of insulin sensitivity and lipid oxidation and, purportedly, in the development of atherosclerosis and coronary heart disease in humans. Objective  To assess prospectively whether plasma adiponectin concentrations are associated with risk of myocardial infarction (MI). Design, Setting, and Participants  Nested case-control study among 18 225 male participants of the Health Professionals Follow-up Study aged 40 to 75 years who were free of diagnosed cardiovascular disease at the time of blood draw (1993-1995). During 6 years of follow-up through January 31, 2000, 266 men subsequently developed nonfatal MI or fatal coronary heart disease. Using risk set sampling, controls were selected in a 2:1 ratio matched for age, date of blood draw, and smoking status (n = 532). Main Outcome Measure  Incidence of nonfatal MI and fatal coronary heart disease by adiponectin level. Results  After adjustment for matched variables, participants in the highest compared with the lowest quintile of adiponectin levels had a significantly decreased risk of MI (relative risk [RR], 0.39; 95% confidence interval [CI], 0.23-0.64; P for trend <.001). Additional adjustment for family history of MI, body mass index, alcohol consumption, physical activity, and history of diabetes and hypertension did not substantively affect this relationship (RR, 0.41; 95% CI, 0.24-0.70; P for trend <.001). Further adjustment for hemoglobin A1c or C-reactive protein levels also had little impact, but additional adjustment for low- and high-density lipoprotein cholesterol levels modestly attenuated this association (RR, 0.56; 95% CI, 0.32-0.99; P for trend = .02). Conclusions  High plasma adiponectin concentrations are associated with lower risk of MI in men. This relationship can be only partly explained by differences in blood lipids and is independent of inflammation and glycemic status.   相似文献
10.
Context  Following percutaneous coronary intervention (PCI), short-term clopidogrel therapy in addition to aspirin leads to greater protection from thrombotic complications than aspirin alone. However, the optimal duration of combination oral antiplatelet therapy is unknown. Also, although current clinical data suggest a benefit for beginning therapy with a clopidogrel loading dose prior to PCI, the practical application of this therapy has not been prospectively studied. Objectives  To evaluate the benefit of long-term (12-month) treatment with clopidogrel after PCI and to determine the benefit of initiating clopidogrel with a preprocedure loading dose, both in addition to aspirin therapy. Design, Setting, and Participants  The Clopidogrel for the Reduction of Events During Observation (CREDO) trial, a randomized, double-blind, placebo-controlled trial conducted among 2116 patients who were to undergo elective PCI or were deemed at high likelihood of undergoing PCI, enrolled at 99 centers in North America from June 1999 through April 2001. Interventions  Patients were randomly assigned to receive a 300-mg clopidogrel loading dose (n = 1053) or placebo (n = 1063) 3 to 24 hours before PCI. Thereafter, all patients received clopidogrel, 75 mg/d, through day 28. From day 29 through 12 months, patients in the loading-dose group received clopidogrel, 75 mg/d, and those in the control group received placebo. Both groups received aspirin throughout the study. Main Outcome Measures  One-year incidence of the composite of death, myocardial infarction (MI), or stroke in the intent-to-treat population; 28-day incidence of the composite of death, MI, or urgent target vessel revascularization in the per-protocol population. Results  At 1 year, long-term clopidogrel therapy was associated with a 26.9% relative reduction in the combined risk of death, MI, or stroke (95% confidence interval [CI], 3.9%-44.4%; P = .02; absolute reduction, 3%). Clopidogrel pretreatment did not significantly reduce the combined risk of death, MI, or urgent target vessel revascularization at 28 days (reduction, 18.5%; 95% CI, -14.2% to 41.8%; P = .23). However, in a prespecified subgroup analysis, patients who received clopidogrel at least 6 hours before PCI experienced a relative risk reduction of 38.6% (95% CI, -1.6% to 62.9%; P = .051) for this end point compared with no reduction with treatment less than 6 hours before PCI. Risk of major bleeding at 1 year increased, but not significantly (8.8% with clopidogrel vs 6.7% with placebo; P = .07). Conclusions  Following PCI, long-term (1-year) clopidogrel therapy significantly reduced the risk of adverse ischemic events. A loading dose of clopidogrel given at least 3 hours before the procedure did not reduce events at 28 days, but subgroup analyses suggest that longer intervals between the loading dose and PCI may reduce events.   相似文献
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